xref: /openbmc/qemu/chardev/char.c (revision 438c78da)
1 /*
2  * QEMU System Emulator
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "qemu/cutils.h"
27 #include "monitor/monitor.h"
28 #include "sysemu/sysemu.h"
29 #include "qemu/config-file.h"
30 #include "qemu/error-report.h"
31 #include "chardev/char.h"
32 #include "qapi/error.h"
33 #include "qapi/qapi-commands-char.h"
34 #include "qapi/qmp/qerror.h"
35 #include "sysemu/replay.h"
36 #include "qemu/help_option.h"
37 #include "qemu/option.h"
38 
39 #include "chardev/char-mux.h"
40 
41 /***********************************************************/
42 /* character device */
43 
44 static Object *get_chardevs_root(void)
45 {
46     return container_get(object_get_root(), "/chardevs");
47 }
48 
49 static void chr_be_event(Chardev *s, int event)
50 {
51     CharBackend *be = s->be;
52 
53     if (!be || !be->chr_event) {
54         return;
55     }
56 
57     be->chr_event(be->opaque, event);
58 }
59 
60 void qemu_chr_be_event(Chardev *s, int event)
61 {
62     /* Keep track if the char device is open */
63     switch (event) {
64         case CHR_EVENT_OPENED:
65             s->be_open = 1;
66             break;
67         case CHR_EVENT_CLOSED:
68             s->be_open = 0;
69             break;
70     }
71 
72     CHARDEV_GET_CLASS(s)->chr_be_event(s, event);
73 }
74 
75 /* Not reporting errors from writing to logfile, as logs are
76  * defined to be "best effort" only */
77 static void qemu_chr_write_log(Chardev *s, const uint8_t *buf, size_t len)
78 {
79     size_t done = 0;
80     ssize_t ret;
81 
82     if (s->logfd < 0) {
83         return;
84     }
85 
86     while (done < len) {
87     retry:
88         ret = write(s->logfd, buf + done, len - done);
89         if (ret == -1 && errno == EAGAIN) {
90             g_usleep(100);
91             goto retry;
92         }
93 
94         if (ret <= 0) {
95             return;
96         }
97         done += ret;
98     }
99 }
100 
101 static int qemu_chr_write_buffer(Chardev *s,
102                                  const uint8_t *buf, int len,
103                                  int *offset, bool write_all)
104 {
105     ChardevClass *cc = CHARDEV_GET_CLASS(s);
106     int res = 0;
107     *offset = 0;
108 
109     qemu_mutex_lock(&s->chr_write_lock);
110     while (*offset < len) {
111     retry:
112         res = cc->chr_write(s, buf + *offset, len - *offset);
113         if (res < 0 && errno == EAGAIN && write_all) {
114             g_usleep(100);
115             goto retry;
116         }
117 
118         if (res <= 0) {
119             break;
120         }
121 
122         *offset += res;
123         if (!write_all) {
124             break;
125         }
126     }
127     if (*offset > 0) {
128         qemu_chr_write_log(s, buf, *offset);
129     }
130     qemu_mutex_unlock(&s->chr_write_lock);
131 
132     return res;
133 }
134 
135 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all)
136 {
137     int offset = 0;
138     int res;
139 
140     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_PLAY) {
141         replay_char_write_event_load(&res, &offset);
142         assert(offset <= len);
143         qemu_chr_write_buffer(s, buf, offset, &offset, true);
144         return res;
145     }
146 
147     res = qemu_chr_write_buffer(s, buf, len, &offset, write_all);
148 
149     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {
150         replay_char_write_event_save(res, offset);
151     }
152 
153     if (res < 0) {
154         return res;
155     }
156     return offset;
157 }
158 
159 int qemu_chr_be_can_write(Chardev *s)
160 {
161     CharBackend *be = s->be;
162 
163     if (!be || !be->chr_can_read) {
164         return 0;
165     }
166 
167     return be->chr_can_read(be->opaque);
168 }
169 
170 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len)
171 {
172     CharBackend *be = s->be;
173 
174     if (be && be->chr_read) {
175         be->chr_read(be->opaque, buf, len);
176     }
177 }
178 
179 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len)
180 {
181     if (qemu_chr_replay(s)) {
182         if (replay_mode == REPLAY_MODE_PLAY) {
183             return;
184         }
185         replay_chr_be_write(s, buf, len);
186     } else {
187         qemu_chr_be_write_impl(s, buf, len);
188     }
189 }
190 
191 void qemu_chr_be_update_read_handlers(Chardev *s,
192                                       GMainContext *context)
193 {
194     ChardevClass *cc = CHARDEV_GET_CLASS(s);
195 
196     s->gcontext = context;
197     if (cc->chr_update_read_handler) {
198         cc->chr_update_read_handler(s);
199     }
200 }
201 
202 int qemu_chr_add_client(Chardev *s, int fd)
203 {
204     return CHARDEV_GET_CLASS(s)->chr_add_client ?
205         CHARDEV_GET_CLASS(s)->chr_add_client(s, fd) : -1;
206 }
207 
208 static void qemu_char_open(Chardev *chr, ChardevBackend *backend,
209                            bool *be_opened, Error **errp)
210 {
211     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
212     /* Any ChardevCommon member would work */
213     ChardevCommon *common = backend ? backend->u.null.data : NULL;
214 
215     if (common && common->has_logfile) {
216         int flags = O_WRONLY | O_CREAT;
217         if (common->has_logappend &&
218             common->logappend) {
219             flags |= O_APPEND;
220         } else {
221             flags |= O_TRUNC;
222         }
223         chr->logfd = qemu_open(common->logfile, flags, 0666);
224         if (chr->logfd < 0) {
225             error_setg_errno(errp, errno,
226                              "Unable to open logfile %s",
227                              common->logfile);
228             return;
229         }
230     }
231 
232     if (cc->open) {
233         cc->open(chr, backend, be_opened, errp);
234     }
235 }
236 
237 static void char_init(Object *obj)
238 {
239     Chardev *chr = CHARDEV(obj);
240 
241     chr->logfd = -1;
242     qemu_mutex_init(&chr->chr_write_lock);
243 }
244 
245 static int null_chr_write(Chardev *chr, const uint8_t *buf, int len)
246 {
247     return len;
248 }
249 
250 static void char_class_init(ObjectClass *oc, void *data)
251 {
252     ChardevClass *cc = CHARDEV_CLASS(oc);
253 
254     cc->chr_write = null_chr_write;
255     cc->chr_be_event = chr_be_event;
256 }
257 
258 static void char_finalize(Object *obj)
259 {
260     Chardev *chr = CHARDEV(obj);
261 
262     if (chr->be) {
263         chr->be->chr = NULL;
264     }
265     g_free(chr->filename);
266     g_free(chr->label);
267     if (chr->logfd != -1) {
268         close(chr->logfd);
269     }
270     qemu_mutex_destroy(&chr->chr_write_lock);
271 }
272 
273 static const TypeInfo char_type_info = {
274     .name = TYPE_CHARDEV,
275     .parent = TYPE_OBJECT,
276     .instance_size = sizeof(Chardev),
277     .instance_init = char_init,
278     .instance_finalize = char_finalize,
279     .abstract = true,
280     .class_size = sizeof(ChardevClass),
281     .class_init = char_class_init,
282 };
283 
284 static int chardev_machine_done_notify_one(Object *child, void *opaque)
285 {
286     Chardev *chr = (Chardev *)child;
287     ChardevClass *class = CHARDEV_GET_CLASS(chr);
288 
289     if (class->chr_machine_done) {
290         return class->chr_machine_done(chr);
291     }
292 
293     return 0;
294 }
295 
296 static void chardev_machine_done_hook(Notifier *notifier, void *unused)
297 {
298     int ret = object_child_foreach(get_chardevs_root(),
299                                    chardev_machine_done_notify_one, NULL);
300 
301     if (ret) {
302         error_report("Failed to call chardev machine_done hooks");
303         exit(1);
304     }
305 }
306 
307 static Notifier chardev_machine_done_notify = {
308     .notify = chardev_machine_done_hook,
309 };
310 
311 static bool qemu_chr_is_busy(Chardev *s)
312 {
313     if (CHARDEV_IS_MUX(s)) {
314         MuxChardev *d = MUX_CHARDEV(s);
315         return d->mux_cnt >= 0;
316     } else {
317         return s->be != NULL;
318     }
319 }
320 
321 int qemu_chr_wait_connected(Chardev *chr, Error **errp)
322 {
323     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
324 
325     if (cc->chr_wait_connected) {
326         return cc->chr_wait_connected(chr, errp);
327     }
328 
329     return 0;
330 }
331 
332 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename,
333                                 bool permit_mux_mon)
334 {
335     char host[65], port[33], width[8], height[8];
336     int pos;
337     const char *p;
338     QemuOpts *opts;
339     Error *local_err = NULL;
340 
341     opts = qemu_opts_create(qemu_find_opts("chardev"), label, 1, &local_err);
342     if (local_err) {
343         error_report_err(local_err);
344         return NULL;
345     }
346 
347     if (strstart(filename, "mon:", &p)) {
348         if (!permit_mux_mon) {
349             error_report("mon: isn't supported in this context");
350             return NULL;
351         }
352         filename = p;
353         qemu_opt_set(opts, "mux", "on", &error_abort);
354         if (strcmp(filename, "stdio") == 0) {
355             /* Monitor is muxed to stdio: do not exit on Ctrl+C by default
356              * but pass it to the guest.  Handle this only for compat syntax,
357              * for -chardev syntax we have special option for this.
358              * This is what -nographic did, redirecting+muxing serial+monitor
359              * to stdio causing Ctrl+C to be passed to guest. */
360             qemu_opt_set(opts, "signal", "off", &error_abort);
361         }
362     }
363 
364     if (strcmp(filename, "null")    == 0 ||
365         strcmp(filename, "pty")     == 0 ||
366         strcmp(filename, "msmouse") == 0 ||
367         strcmp(filename, "wctablet") == 0 ||
368         strcmp(filename, "braille") == 0 ||
369         strcmp(filename, "testdev") == 0 ||
370         strcmp(filename, "stdio")   == 0) {
371         qemu_opt_set(opts, "backend", filename, &error_abort);
372         return opts;
373     }
374     if (strstart(filename, "vc", &p)) {
375         qemu_opt_set(opts, "backend", "vc", &error_abort);
376         if (*p == ':') {
377             if (sscanf(p+1, "%7[0-9]x%7[0-9]", width, height) == 2) {
378                 /* pixels */
379                 qemu_opt_set(opts, "width", width, &error_abort);
380                 qemu_opt_set(opts, "height", height, &error_abort);
381             } else if (sscanf(p+1, "%7[0-9]Cx%7[0-9]C", width, height) == 2) {
382                 /* chars */
383                 qemu_opt_set(opts, "cols", width, &error_abort);
384                 qemu_opt_set(opts, "rows", height, &error_abort);
385             } else {
386                 goto fail;
387             }
388         }
389         return opts;
390     }
391     if (strcmp(filename, "con:") == 0) {
392         qemu_opt_set(opts, "backend", "console", &error_abort);
393         return opts;
394     }
395     if (strstart(filename, "COM", NULL)) {
396         qemu_opt_set(opts, "backend", "serial", &error_abort);
397         qemu_opt_set(opts, "path", filename, &error_abort);
398         return opts;
399     }
400     if (strstart(filename, "file:", &p)) {
401         qemu_opt_set(opts, "backend", "file", &error_abort);
402         qemu_opt_set(opts, "path", p, &error_abort);
403         return opts;
404     }
405     if (strstart(filename, "pipe:", &p)) {
406         qemu_opt_set(opts, "backend", "pipe", &error_abort);
407         qemu_opt_set(opts, "path", p, &error_abort);
408         return opts;
409     }
410     if (strstart(filename, "tcp:", &p) ||
411         strstart(filename, "telnet:", &p) ||
412         strstart(filename, "tn3270:", &p) ||
413         strstart(filename, "websocket:", &p)) {
414         if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
415             host[0] = 0;
416             if (sscanf(p, ":%32[^,]%n", port, &pos) < 1)
417                 goto fail;
418         }
419         qemu_opt_set(opts, "backend", "socket", &error_abort);
420         qemu_opt_set(opts, "host", host, &error_abort);
421         qemu_opt_set(opts, "port", port, &error_abort);
422         if (p[pos] == ',') {
423             qemu_opts_do_parse(opts, p+pos+1, NULL, &local_err);
424             if (local_err) {
425                 error_report_err(local_err);
426                 goto fail;
427             }
428         }
429         if (strstart(filename, "telnet:", &p)) {
430             qemu_opt_set(opts, "telnet", "on", &error_abort);
431         } else if (strstart(filename, "tn3270:", &p)) {
432             qemu_opt_set(opts, "tn3270", "on", &error_abort);
433         } else if (strstart(filename, "websocket:", &p)) {
434             qemu_opt_set(opts, "websocket", "on", &error_abort);
435         }
436         return opts;
437     }
438     if (strstart(filename, "udp:", &p)) {
439         qemu_opt_set(opts, "backend", "udp", &error_abort);
440         if (sscanf(p, "%64[^:]:%32[^@,]%n", host, port, &pos) < 2) {
441             host[0] = 0;
442             if (sscanf(p, ":%32[^@,]%n", port, &pos) < 1) {
443                 goto fail;
444             }
445         }
446         qemu_opt_set(opts, "host", host, &error_abort);
447         qemu_opt_set(opts, "port", port, &error_abort);
448         if (p[pos] == '@') {
449             p += pos + 1;
450             if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
451                 host[0] = 0;
452                 if (sscanf(p, ":%32[^,]%n", port, &pos) < 1) {
453                     goto fail;
454                 }
455             }
456             qemu_opt_set(opts, "localaddr", host, &error_abort);
457             qemu_opt_set(opts, "localport", port, &error_abort);
458         }
459         return opts;
460     }
461     if (strstart(filename, "unix:", &p)) {
462         qemu_opt_set(opts, "backend", "socket", &error_abort);
463         qemu_opts_do_parse(opts, p, "path", &local_err);
464         if (local_err) {
465             error_report_err(local_err);
466             goto fail;
467         }
468         return opts;
469     }
470     if (strstart(filename, "/dev/parport", NULL) ||
471         strstart(filename, "/dev/ppi", NULL)) {
472         qemu_opt_set(opts, "backend", "parallel", &error_abort);
473         qemu_opt_set(opts, "path", filename, &error_abort);
474         return opts;
475     }
476     if (strstart(filename, "/dev/", NULL)) {
477         qemu_opt_set(opts, "backend", "serial", &error_abort);
478         qemu_opt_set(opts, "path", filename, &error_abort);
479         return opts;
480     }
481 
482 fail:
483     qemu_opts_del(opts);
484     return NULL;
485 }
486 
487 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend)
488 {
489     const char *logfile = qemu_opt_get(opts, "logfile");
490 
491     backend->has_logfile = logfile != NULL;
492     backend->logfile = g_strdup(logfile);
493 
494     backend->has_logappend = true;
495     backend->logappend = qemu_opt_get_bool(opts, "logappend", false);
496 }
497 
498 static const ChardevClass *char_get_class(const char *driver, Error **errp)
499 {
500     ObjectClass *oc;
501     const ChardevClass *cc;
502     char *typename = g_strdup_printf("chardev-%s", driver);
503 
504     oc = object_class_by_name(typename);
505     g_free(typename);
506 
507     if (!object_class_dynamic_cast(oc, TYPE_CHARDEV)) {
508         error_setg(errp, "'%s' is not a valid char driver name", driver);
509         return NULL;
510     }
511 
512     if (object_class_is_abstract(oc)) {
513         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "driver",
514                    "abstract device type");
515         return NULL;
516     }
517 
518     cc = CHARDEV_CLASS(oc);
519     if (cc->internal) {
520         error_setg(errp, "'%s' is not a valid char driver name", driver);
521         return NULL;
522     }
523 
524     return cc;
525 }
526 
527 static const struct ChardevAlias {
528     const char *typename;
529     const char *alias;
530 } chardev_alias_table[] = {
531 #ifdef HAVE_CHARDEV_PARPORT
532     { "parallel", "parport" },
533 #endif
534 #ifdef HAVE_CHARDEV_SERIAL
535     { "serial", "tty" },
536 #endif
537 };
538 
539 typedef struct ChadevClassFE {
540     void (*fn)(const char *name, void *opaque);
541     void *opaque;
542 } ChadevClassFE;
543 
544 static void
545 chardev_class_foreach(ObjectClass *klass, void *opaque)
546 {
547     ChadevClassFE *fe = opaque;
548 
549     assert(g_str_has_prefix(object_class_get_name(klass), "chardev-"));
550     if (CHARDEV_CLASS(klass)->internal) {
551         return;
552     }
553 
554     fe->fn(object_class_get_name(klass) + 8, fe->opaque);
555 }
556 
557 static void
558 chardev_name_foreach(void (*fn)(const char *name, void *opaque), void *opaque)
559 {
560     ChadevClassFE fe = { .fn = fn, .opaque = opaque };
561     int i;
562 
563     object_class_foreach(chardev_class_foreach, TYPE_CHARDEV, false, &fe);
564 
565     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
566         fn(chardev_alias_table[i].alias, opaque);
567     }
568 }
569 
570 static void
571 help_string_append(const char *name, void *opaque)
572 {
573     GString *str = opaque;
574 
575     g_string_append_printf(str, "\n%s", name);
576 }
577 
578 static const char *chardev_alias_translate(const char *name)
579 {
580     int i;
581     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
582         if (g_strcmp0(chardev_alias_table[i].alias, name) == 0) {
583             return chardev_alias_table[i].typename;
584         }
585     }
586     return name;
587 }
588 
589 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts, Error **errp)
590 {
591     Error *local_err = NULL;
592     const ChardevClass *cc;
593     ChardevBackend *backend = NULL;
594     const char *name = chardev_alias_translate(qemu_opt_get(opts, "backend"));
595 
596     if (name == NULL) {
597         error_setg(errp, "chardev: \"%s\" missing backend",
598                    qemu_opts_id(opts));
599         return NULL;
600     }
601 
602     cc = char_get_class(name, errp);
603     if (cc == NULL) {
604         return NULL;
605     }
606 
607     backend = g_new0(ChardevBackend, 1);
608     backend->type = CHARDEV_BACKEND_KIND_NULL;
609 
610     if (cc->parse) {
611         cc->parse(opts, backend, &local_err);
612         if (local_err) {
613             error_propagate(errp, local_err);
614             qapi_free_ChardevBackend(backend);
615             return NULL;
616         }
617     } else {
618         ChardevCommon *ccom = g_new0(ChardevCommon, 1);
619         qemu_chr_parse_common(opts, ccom);
620         backend->u.null.data = ccom; /* Any ChardevCommon member would work */
621     }
622 
623     return backend;
624 }
625 
626 Chardev *qemu_chr_new_from_opts(QemuOpts *opts, Error **errp)
627 {
628     const ChardevClass *cc;
629     Chardev *chr = NULL;
630     ChardevBackend *backend = NULL;
631     const char *name = chardev_alias_translate(qemu_opt_get(opts, "backend"));
632     const char *id = qemu_opts_id(opts);
633     char *bid = NULL;
634 
635     if (name && is_help_option(name)) {
636         GString *str = g_string_new("");
637 
638         chardev_name_foreach(help_string_append, str);
639 
640         error_printf("Available chardev backend types: %s\n", str->str);
641         g_string_free(str, true);
642         return NULL;
643     }
644 
645     if (id == NULL) {
646         error_setg(errp, "chardev: no id specified");
647         return NULL;
648     }
649 
650     backend = qemu_chr_parse_opts(opts, errp);
651     if (backend == NULL) {
652         return NULL;
653     }
654 
655     cc = char_get_class(name, errp);
656     if (cc == NULL) {
657         goto out;
658     }
659 
660     if (qemu_opt_get_bool(opts, "mux", 0)) {
661         bid = g_strdup_printf("%s-base", id);
662     }
663 
664     chr = qemu_chardev_new(bid ? bid : id,
665                            object_class_get_name(OBJECT_CLASS(cc)),
666                            backend, errp);
667 
668     if (chr == NULL) {
669         goto out;
670     }
671 
672     if (bid) {
673         Chardev *mux;
674         qapi_free_ChardevBackend(backend);
675         backend = g_new0(ChardevBackend, 1);
676         backend->type = CHARDEV_BACKEND_KIND_MUX;
677         backend->u.mux.data = g_new0(ChardevMux, 1);
678         backend->u.mux.data->chardev = g_strdup(bid);
679         mux = qemu_chardev_new(id, TYPE_CHARDEV_MUX, backend, errp);
680         if (mux == NULL) {
681             object_unparent(OBJECT(chr));
682             chr = NULL;
683             goto out;
684         }
685         chr = mux;
686     }
687 
688 out:
689     qapi_free_ChardevBackend(backend);
690     g_free(bid);
691     return chr;
692 }
693 
694 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename,
695                                bool permit_mux_mon)
696 {
697     const char *p;
698     Chardev *chr;
699     QemuOpts *opts;
700     Error *err = NULL;
701 
702     if (strstart(filename, "chardev:", &p)) {
703         return qemu_chr_find(p);
704     }
705 
706     opts = qemu_chr_parse_compat(label, filename, permit_mux_mon);
707     if (!opts)
708         return NULL;
709 
710     chr = qemu_chr_new_from_opts(opts, &err);
711     if (!chr) {
712         error_report_err(err);
713         goto out;
714     }
715 
716     if (qemu_opt_get_bool(opts, "mux", 0)) {
717         assert(permit_mux_mon);
718         monitor_init(chr, MONITOR_USE_READLINE);
719     }
720 
721 out:
722     qemu_opts_del(opts);
723     return chr;
724 }
725 
726 static Chardev *qemu_chr_new_permit_mux_mon(const char *label,
727                                           const char *filename,
728                                           bool permit_mux_mon)
729 {
730     Chardev *chr;
731     chr = qemu_chr_new_noreplay(label, filename, permit_mux_mon);
732     if (chr) {
733         if (replay_mode != REPLAY_MODE_NONE) {
734             qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_REPLAY);
735         }
736         if (qemu_chr_replay(chr) && CHARDEV_GET_CLASS(chr)->chr_ioctl) {
737             error_report("Replay: ioctl is not supported "
738                          "for serial devices yet");
739         }
740         replay_register_char_driver(chr);
741     }
742     return chr;
743 }
744 
745 Chardev *qemu_chr_new(const char *label, const char *filename)
746 {
747     return qemu_chr_new_permit_mux_mon(label, filename, false);
748 }
749 
750 Chardev *qemu_chr_new_mux_mon(const char *label, const char *filename)
751 {
752     return qemu_chr_new_permit_mux_mon(label, filename, true);
753 }
754 
755 static int qmp_query_chardev_foreach(Object *obj, void *data)
756 {
757     Chardev *chr = CHARDEV(obj);
758     ChardevInfoList **list = data;
759     ChardevInfoList *info = g_malloc0(sizeof(*info));
760 
761     info->value = g_malloc0(sizeof(*info->value));
762     info->value->label = g_strdup(chr->label);
763     info->value->filename = g_strdup(chr->filename);
764     info->value->frontend_open = chr->be && chr->be->fe_open;
765 
766     info->next = *list;
767     *list = info;
768 
769     return 0;
770 }
771 
772 ChardevInfoList *qmp_query_chardev(Error **errp)
773 {
774     ChardevInfoList *chr_list = NULL;
775 
776     object_child_foreach(get_chardevs_root(),
777                          qmp_query_chardev_foreach, &chr_list);
778 
779     return chr_list;
780 }
781 
782 static void
783 qmp_prepend_backend(const char *name, void *opaque)
784 {
785     ChardevBackendInfoList **list = opaque;
786     ChardevBackendInfoList *info = g_malloc0(sizeof(*info));
787 
788     info->value = g_malloc0(sizeof(*info->value));
789     info->value->name = g_strdup(name);
790     info->next = *list;
791     *list = info;
792 }
793 
794 ChardevBackendInfoList *qmp_query_chardev_backends(Error **errp)
795 {
796     ChardevBackendInfoList *backend_list = NULL;
797 
798     chardev_name_foreach(qmp_prepend_backend, &backend_list);
799 
800     return backend_list;
801 }
802 
803 Chardev *qemu_chr_find(const char *name)
804 {
805     Object *obj = object_resolve_path_component(get_chardevs_root(), name);
806 
807     return obj ? CHARDEV(obj) : NULL;
808 }
809 
810 QemuOptsList qemu_chardev_opts = {
811     .name = "chardev",
812     .implied_opt_name = "backend",
813     .head = QTAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
814     .desc = {
815         {
816             .name = "backend",
817             .type = QEMU_OPT_STRING,
818         },{
819             .name = "path",
820             .type = QEMU_OPT_STRING,
821         },{
822             .name = "host",
823             .type = QEMU_OPT_STRING,
824         },{
825             .name = "port",
826             .type = QEMU_OPT_STRING,
827         },{
828             .name = "fd",
829             .type = QEMU_OPT_STRING,
830         },{
831             .name = "localaddr",
832             .type = QEMU_OPT_STRING,
833         },{
834             .name = "localport",
835             .type = QEMU_OPT_STRING,
836         },{
837             .name = "to",
838             .type = QEMU_OPT_NUMBER,
839         },{
840             .name = "ipv4",
841             .type = QEMU_OPT_BOOL,
842         },{
843             .name = "ipv6",
844             .type = QEMU_OPT_BOOL,
845         },{
846             .name = "wait",
847             .type = QEMU_OPT_BOOL,
848         },{
849             .name = "server",
850             .type = QEMU_OPT_BOOL,
851         },{
852             .name = "delay",
853             .type = QEMU_OPT_BOOL,
854         },{
855             .name = "reconnect",
856             .type = QEMU_OPT_NUMBER,
857         },{
858             .name = "telnet",
859             .type = QEMU_OPT_BOOL,
860         },{
861             .name = "tn3270",
862             .type = QEMU_OPT_BOOL,
863         },{
864             .name = "tls-creds",
865             .type = QEMU_OPT_STRING,
866         },{
867             .name = "websocket",
868             .type = QEMU_OPT_BOOL,
869         },{
870             .name = "width",
871             .type = QEMU_OPT_NUMBER,
872         },{
873             .name = "height",
874             .type = QEMU_OPT_NUMBER,
875         },{
876             .name = "cols",
877             .type = QEMU_OPT_NUMBER,
878         },{
879             .name = "rows",
880             .type = QEMU_OPT_NUMBER,
881         },{
882             .name = "mux",
883             .type = QEMU_OPT_BOOL,
884         },{
885             .name = "signal",
886             .type = QEMU_OPT_BOOL,
887         },{
888             .name = "name",
889             .type = QEMU_OPT_STRING,
890         },{
891             .name = "debug",
892             .type = QEMU_OPT_NUMBER,
893         },{
894             .name = "size",
895             .type = QEMU_OPT_SIZE,
896         },{
897             .name = "chardev",
898             .type = QEMU_OPT_STRING,
899         },{
900             .name = "append",
901             .type = QEMU_OPT_BOOL,
902         },{
903             .name = "logfile",
904             .type = QEMU_OPT_STRING,
905         },{
906             .name = "logappend",
907             .type = QEMU_OPT_BOOL,
908         },
909         { /* end of list */ }
910     },
911 };
912 
913 bool qemu_chr_has_feature(Chardev *chr,
914                           ChardevFeature feature)
915 {
916     return test_bit(feature, chr->features);
917 }
918 
919 void qemu_chr_set_feature(Chardev *chr,
920                            ChardevFeature feature)
921 {
922     return set_bit(feature, chr->features);
923 }
924 
925 Chardev *qemu_chardev_new(const char *id, const char *typename,
926                           ChardevBackend *backend,
927                           Error **errp)
928 {
929     Object *obj;
930     Chardev *chr = NULL;
931     Error *local_err = NULL;
932     bool be_opened = true;
933 
934     assert(g_str_has_prefix(typename, "chardev-"));
935 
936     obj = object_new(typename);
937     chr = CHARDEV(obj);
938     chr->label = g_strdup(id);
939 
940     qemu_char_open(chr, backend, &be_opened, &local_err);
941     if (local_err) {
942         goto end;
943     }
944 
945     if (!chr->filename) {
946         chr->filename = g_strdup(typename + 8);
947     }
948     if (be_opened) {
949         qemu_chr_be_event(chr, CHR_EVENT_OPENED);
950     }
951 
952     if (id) {
953         object_property_add_child(get_chardevs_root(), id, obj, &local_err);
954         if (local_err) {
955             goto end;
956         }
957         object_unref(obj);
958     }
959 
960 end:
961     if (local_err) {
962         error_propagate(errp, local_err);
963         object_unref(obj);
964         return NULL;
965     }
966 
967     return chr;
968 }
969 
970 ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
971                                Error **errp)
972 {
973     const ChardevClass *cc;
974     ChardevReturn *ret;
975     Chardev *chr;
976 
977     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
978     if (!cc) {
979         return NULL;
980     }
981 
982     chr = qemu_chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
983                            backend, errp);
984     if (!chr) {
985         return NULL;
986     }
987 
988     ret = g_new0(ChardevReturn, 1);
989     if (CHARDEV_IS_PTY(chr)) {
990         ret->pty = g_strdup(chr->filename + 4);
991         ret->has_pty = true;
992     }
993 
994     return ret;
995 }
996 
997 ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
998                                   Error **errp)
999 {
1000     CharBackend *be;
1001     const ChardevClass *cc;
1002     Chardev *chr, *chr_new;
1003     bool closed_sent = false;
1004     ChardevReturn *ret;
1005 
1006     chr = qemu_chr_find(id);
1007     if (!chr) {
1008         error_setg(errp, "Chardev '%s' does not exist", id);
1009         return NULL;
1010     }
1011 
1012     if (CHARDEV_IS_MUX(chr)) {
1013         error_setg(errp, "Mux device hotswap not supported yet");
1014         return NULL;
1015     }
1016 
1017     if (qemu_chr_replay(chr)) {
1018         error_setg(errp,
1019             "Chardev '%s' cannot be changed in record/replay mode", id);
1020         return NULL;
1021     }
1022 
1023     be = chr->be;
1024     if (!be) {
1025         /* easy case */
1026         object_unparent(OBJECT(chr));
1027         return qmp_chardev_add(id, backend, errp);
1028     }
1029 
1030     if (!be->chr_be_change) {
1031         error_setg(errp, "Chardev user does not support chardev hotswap");
1032         return NULL;
1033     }
1034 
1035     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
1036     if (!cc) {
1037         return NULL;
1038     }
1039 
1040     chr_new = qemu_chardev_new(NULL, object_class_get_name(OBJECT_CLASS(cc)),
1041                                backend, errp);
1042     if (!chr_new) {
1043         return NULL;
1044     }
1045     chr_new->label = g_strdup(id);
1046 
1047     if (chr->be_open && !chr_new->be_open) {
1048         qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
1049         closed_sent = true;
1050     }
1051 
1052     chr->be = NULL;
1053     qemu_chr_fe_init(be, chr_new, &error_abort);
1054 
1055     if (be->chr_be_change(be->opaque) < 0) {
1056         error_setg(errp, "Chardev '%s' change failed", chr_new->label);
1057         chr_new->be = NULL;
1058         qemu_chr_fe_init(be, chr, &error_abort);
1059         if (closed_sent) {
1060             qemu_chr_be_event(chr, CHR_EVENT_OPENED);
1061         }
1062         object_unref(OBJECT(chr_new));
1063         return NULL;
1064     }
1065 
1066     object_unparent(OBJECT(chr));
1067     object_property_add_child(get_chardevs_root(), chr_new->label,
1068                               OBJECT(chr_new), &error_abort);
1069     object_unref(OBJECT(chr_new));
1070 
1071     ret = g_new0(ChardevReturn, 1);
1072     if (CHARDEV_IS_PTY(chr_new)) {
1073         ret->pty = g_strdup(chr_new->filename + 4);
1074         ret->has_pty = true;
1075     }
1076 
1077     return ret;
1078 }
1079 
1080 void qmp_chardev_remove(const char *id, Error **errp)
1081 {
1082     Chardev *chr;
1083 
1084     chr = qemu_chr_find(id);
1085     if (chr == NULL) {
1086         error_setg(errp, "Chardev '%s' not found", id);
1087         return;
1088     }
1089     if (qemu_chr_is_busy(chr)) {
1090         error_setg(errp, "Chardev '%s' is busy", id);
1091         return;
1092     }
1093     if (qemu_chr_replay(chr)) {
1094         error_setg(errp,
1095             "Chardev '%s' cannot be unplugged in record/replay mode", id);
1096         return;
1097     }
1098     object_unparent(OBJECT(chr));
1099 }
1100 
1101 void qmp_chardev_send_break(const char *id, Error **errp)
1102 {
1103     Chardev *chr;
1104 
1105     chr = qemu_chr_find(id);
1106     if (chr == NULL) {
1107         error_setg(errp, "Chardev '%s' not found", id);
1108         return;
1109     }
1110     qemu_chr_be_event(chr, CHR_EVENT_BREAK);
1111 }
1112 
1113 /*
1114  * Add a timeout callback for the chardev (in milliseconds), return
1115  * the GSource object created. Please use this to add timeout hook for
1116  * chardev instead of g_timeout_add() and g_timeout_add_seconds(), to
1117  * make sure the gcontext that the task bound to is correct.
1118  */
1119 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
1120                                  GSourceFunc func, void *private)
1121 {
1122     GSource *source = g_timeout_source_new(ms);
1123 
1124     assert(func);
1125     g_source_set_callback(source, func, private, NULL);
1126     g_source_attach(source, chr->gcontext);
1127 
1128     return source;
1129 }
1130 
1131 void qemu_chr_cleanup(void)
1132 {
1133     object_unparent(get_chardevs_root());
1134 }
1135 
1136 static void register_types(void)
1137 {
1138     type_register_static(&char_type_info);
1139 
1140     /* this must be done after machine init, since we register FEs with muxes
1141      * as part of realize functions like serial_isa_realizefn when -nographic
1142      * is specified
1143      */
1144     qemu_add_machine_init_done_notifier(&chardev_machine_done_notify);
1145 }
1146 
1147 type_init(register_types);
1148